Cleanup: Remove unneeded forward declarations in ppapi.

ppapi/native_client/src/trusted/plugin/desc_based_handle.h

 /*
  * Copyright (c) 2011 The Chromium Authors. All rights reserved.
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 // OBSOLETE -- this class provides support for passing NaClDescs between
 // plugin instances.  This support only exists in SRPC-mode plugins.
 // TODO(polina): remove when SRPC descriptor passing is removed.
 
 #ifndef NATIVE_CLIENT_SRC_TRUSTED_PLUGIN_DESC_BASED_HANDLE_H_
 #define NATIVE_CLIENT_SRC_TRUSTED_PLUGIN_DESC_BASED_HANDLE_H_
 
 #include <stdio.h>
 #include <map>
 
 #include "native_client/src/include/nacl_macros.h"
 #include "native_client/src/include/nacl_scoped_ptr.h"
 #include "native_client/src/trusted/desc/nacl_desc_wrapper.h"
 #include "native_client/src/trusted/plugin/utility.h"
 
 struct NaClDesc;
 
 namespace nacl {
 class DescWrapper;
 }  // namespace nacl
 
 namespace plugin {
 
-class Plugin;
-
 // DescBasedHandles are used to convey NaClDesc objects through JavaScript.
 class DescBasedHandle {
  public:
   // Creates a new DescBasedHandle using the specified plugin and wrapper.
   // Returns NULL if either plugin or wrapper is NULL.
   static DescBasedHandle* New(nacl::DescWrapper* wrapper);
   ~DescBasedHandle();
 
   // Because the factory ensured that wrapper was not NULL, dereferencing it
   // here is always safe.
   NaClDesc* desc() const { return wrapper_->desc(); }
 
  private:
   NACL_DISALLOW_COPY_AND_ASSIGN(DescBasedHandle);
   explicit DescBasedHandle(nacl::DescWrapper* wrapper);
   nacl::scoped_ptr<nacl::DescWrapper> wrapper_;
 };
 
 }  // namespace plugin
 
 #endif  // NATIVE_CLIENT_SRC_TRUSTED_PLUGIN_DESC_BASED_HANDLE_H_